Eduard lattber



' NITED STATES PATENT OFFICE.

EDUARD LAUBER, OF TORRE-PELLIOE, AND LUIGI CABERTI, OF MESSINA, ITALY, ASSIGNORS TO THE FARBENFABRIKEN, VORMALS FR. BAYER &

00., or ELBERFELD, GERMANY.

success OF DYEING.

SPECIFICATION forming part of Letters Patent No. 542,022, dated July 2, 1895. Application filed April 5, 1895. Serial No. 544,672. (No specimens.) Patented in Germany June 9, 1884, No. 79,802.

To ctZZ whom it may concern.-

Be it known that we, EDUARD LAUBER, a citizen of Germany, residing at Torre-Pellice, Italy, and LUIGI GABERTI, a citizen of Italy,

residing at Messina, Italy, doctors of philosophy, chemists, assignors to the FARBEN: FABRIKEN, voRMALs FR. BAYER & 00., of Elberfeld, Prussia, Germany, have invented a beta naphthol, together with antimonious oxicl (Sb O in an alkaline solution, and subsequently allowing any diazo compound to act in the usual well-known manner on the material treated in the above manner.

The method used hithertofor producing by means of beta-naphthol insoluble azo dyes on the cotton material consists in padding the material with an alkaline solution of betanaphthol, drying the impregnated cotton ma- 3o terial, and finally combining the beta-naphthol on the fiber with any suitable diazo compound. This method, however, is very defective in many regards, owing to the property of beta-naphthol when fixed on the fiber to be decomposed. Therefore it is very difficult to produce clear and intense shades on such cotton material containing beta-naphthol partly decomposed. According to our researches, however, solutions of alkaline as salts of beta-naphthol by themselves, or when used for impregnating the cotton fiber, do not undergo any decomposition if antimonious oxid is present. This latter substance has the remarkable property to keep the betanaphthol also when on the fiber in good and stable form during a long time. In the like manner beta'naphthol in alkline solutions, to which antimonious oxid is added, remains undecomposed, while-beta naphthol, when dissolved in alkaline solution without an addition of antimonious oxid, soon becomes yellowish-brown owing to the gradual decomposition. Our invention, therefore, is of the greatest value, for every printer will now prefer our durable beta-naphthol solution to 5 5 those solutions hitherto in use and not containing antimonious oxid.

In preparing our betanaphthol solution, which we briefly term as naphthol treparation, we can proceed as follows: The solution in water of any antimonious salt, as for example, the double salt of fiuorid of antimony with the fluorid of soda (SbFl NaFl) is treated with the necessary quantity of so- 7 dium carbonate solution. The resulting precipitate, which is antimonious hydroxid, is carefully decanted, nine parts, by weight, of the resulting mass are well mixed with 13.1 parts, by'weight, of glycerin (28 Baum) or other suitable dilutant, and 13.2 parts, by weight, of the sodium salt of beta-naphthol. Athick paste is thus obtained which is finally mixed with asuitable quantity of dilute sodalye, (for example, 20 Baum,) under continuous stirring. After this operation a thick liq- 7 5 uid is obtained which is now fit for practical use.

Of course we do not limit ourselves to the aforesaid proportions, as the same may be varied according to the particular modes of use. Such modifications do not alter the na ture of this invention, which generally relates to the use of beta-naphthol, together with antimonious oxid. Other suitable salts of antimony may be usedfor obtaining the antimonious oxide.

Having now described our invention and in what manner the same is to be performed, what we claim as new, and desire to secure by Letters Patent, is-- 1. The process of dyeing fabrics, which connames in the presence of two subscribing sists, in first treating such fabrics with beta witnesses.

naphthol and antimonious oxid in alkaline EDUARD LAUBER. solution, and in finally treating the thus LUIGI GABERTI. 5 treated fabric with diazo compounds, snbstantially as described. Vitnesses to signature of Eduard Lauber:

2. The new composition of matter hereinbe- J ULES ELTER, fore described, consisting of a solution or ZERRERO GIOVANNI. mixture containing beta naphthol and anti- Witnesses to signature of Luigi Oaberti: Io monious oxid, substantially as described. ORIN AOKAND,

In testimony whereof we have signed our GIOVANNI BURTBEG. 

